python - newbie Django smart/chained menu trouble -

i trying make chained select menu, have model:

from django.db import models  class health_plan(models.model):     name = models.charfield(max_length=15)  class doctors_list(models.model):     name = models.charfield(max_length=30)     specialty = models.charfield(max_length=15)     health_plans = models.manytomanyfield(health_plan, related_name="doctors")     location = models.charfield(max_length=15)      def __unicode__(self):         return self.name 

and forms.py:

class specform(modelform):     = doctors_list.objects.values_list('specialty', flat=true)     unique = [('---------------','---------------')] + [(i,i) in set(a)]     specialty = forms.choicefield(choices=unique)     class meta:         model = doctors_list  class healthform(modelform):     hplan = chainedforeignkey(         health_plan,          chained_field="specialty",         chained_model_field="specialty",          show_all=false,          auto_choose=true     )   

my urls.py:

from django.conf.urls import patterns, include, url testapp.views import spec_form testapp.views import health_form  django.contrib import admin admin.autodiscover()  urlpatterns = patterns('',     # examples:     url(r'^$', 'medbook.views.home', name='home'),     # url(r'^medbook/', include('medbook.foo.urls')),     url(r'^admin/doc/', include('django.contrib.admindocs.urls')),     url(r'^admin/', include(admin.site.urls)),     url(r'^hello/$',  spec_form),     url(r'^hello/$',  health_form), ) 

and views.py:

from django.shortcuts import render_to_response  testapp.forms import specform testapp.forms import healthform  def spec_form (request):     if request.method == 'post':         form = specform(request.post)         if form.is_valid():             form.save()     else:         form = specform()      return render_to_response('hello.html', {'form':form})  def health_form (request):      if request.method == 'post':         form = healthform(request.post)         if form.is_valid():             form.save()     else:         form = specform()     return render_to_response('hello.html', {'form':form}) 

i new django , find tricky. user must select 1 specialty, , should appear health_plans cover specialty.

the health_plans have manytomany relationship doctors. when person chooses specialty, script should check wich doctors belong specialty , retrieve health plans hold doctors.

so far thing in menu is: health_plan object health_plan object health_plan object

i hope made clear, code isn't.

any kindly appreciated

this has nothing chained selects, , of code here irrelevant. issue that, while doctors_list has __unicode__ method, health_plan not. define 1 model too.

(also note usual style model names capwords: doctorslist , healthplan. although former refers single doctor, should doctor.)